Traction-engine.



B. HOLT.

TRACTION 'BNGINEL v APPLICATION mum we. 17, 1909 1 ,026,090, PatentedMay 14, 1912.

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B. HOLT. TRACTION ENGINE.

APPLICATION FILED AUG.17, 1909. 1,026,090.

4 SHEETS-SHEET 3.

U illllllllllllnllllllllllll Patented May 14, 1912. 0

B. HOLT.

TRACTION ENGINE. APPLICATION FILED we. 17,1909.

Patented May 14, 1912.

4-. SHEETS-SHEET 4.

UNITED STATES PATENT oFF -on BENJAMTNHOLT, or s'rocx'ron, chamomi e,

TRACTION-ENGINE.

Application filed August The invention consists of the parts'a'nd -theconstruction and combination of parts as" hereinafter more fullydescribed and claimed, having reference to the accompany-v ing drawings,in which Figure 1 is a plan view of the improved engine. Fig. 2 is aside elevationof the same. Fig. 3 is a detailed section of therack-shifting mechanism. Fig. 4 shows the machine adjusted to run in ahollow. Fig. 5 shows the machine adjusted so that the traction belt isabove the level of the side runners. Fig. this an end view of themachine. Fig. 7 shows the'machine adjusted to run upon a hillside, withthe main frame horizontal. Fig. 8 is a detail showing the roller truckin end view, and shows the side wheel attached. Fig. 9 is a side viewshowing the side runner driving gears and chain, and showsdiagrammatically a steam boiler and engine for driving the tractionwheel. Fi' 10 is a modified form of drive gears for'si e runner. Fig. 11is a sectional view of the internal gear.

In some sections of the country very extensive areas are utilized forvineyards or orchards. The clear space between the parallel rows ofvines or trees is frequently not more than six feet, and the harrowingand plowing of the soil is very slow and expensive when horse-power 1sused.

I have constructed and operated a special design of traction enginewhich is particu' larly applicable for use in narrow spaces and overuneven ground, and-which may readily be adapted to general tractionwork.

The invention embodies a main frame comprising two longitudinal beams orsills '2, suitably spaced apart by -th'e transverse ties or girders 3.,Suitable steering wheels 4, which may be either of the turn table orcenter king-boltitype, are connected with the Specification of-Letterslatent.

Patented May 14, 1912.

17, 1900. Serial No. 513,800.

tongue 5; these steering wheels supporting only a small portion of theweight of the vehicle. The steering is controlled from wheel 4. Theprincipal weight of the vehicle is carried upon a central,longitudinally extending, flexible, driven, endless tread-belt 6, toWhlCll power is imparted by a master sprocket 27 fast on shaft 8, whichis journaled upon the beams 2 of the frame. The belt 6 is mounted sothat it travels centrally betweenthe beams 2, passing over a drivingpulley 7 on shaft 8, and around a forward loosely running guide pulley 9on shaft 11, which latter is mounted in suitable journals 12 secured tothe main frame beams 2. The tread portion proper or ground run of thetrack belt 6 between the two pulleys 7-9 supportsthe rincipal weight ofthe machine on the ro lers 13 journaled uponatruck 18 which is yieldablyconnected to the beams 2 by means of spring 13. Power to propel thetractionbelt 6 is obtained from a suitable motor or source of power '14supported-centrally with and upon the forward elutcli lti 'operated bylever 17 the rear end of shaft 15 having mounted upon it a bevel pinion18 which isshiftable by lever 21 into engagement with either of gears 19or 20 sebracket 23 of the sill, for the purpose of In order to allow theshaft 15 to have a slight oscillatin motion, I have provided a shaft 22carries a pinion sprocket 25, and bjjemeans of a chain 26 running to asprocket- 27 on shaft 8, the belt 6 is driven,

this desi n and arrangement-of parts'I have produce since the tractionmember or supporting belt is placed cent-rally of the frame,.and may-bemade as long approximate y under the center of .ciency is obtained forso narrow a machine.

To accommodatethe engine to various inequalities, or formations of thesurface of the soil, and to maintain it upright under all conditions, Ihave provided adjustable sideaxles 28located about centrally of thelength of cross-beam end of the main sills 2. A driveshaft-15v as isdesirable, and since it is I wig of the load, greatstability andtractive e the frameand pivoted at 29v to the -3. The outer ends oftheiaxles may be chupled with the motor 14 by the cureduponcounter-shaft. 22 journaled on a.

driving. the machine backward 01 f0I'W8.Id.-

universal or 0t er suitable joint 24. The

05 itszdirection of t-ravelbeing determined by the gears 19 or- 20. andthe pinion 18. -By

a machine of minimum width i are adapted to carry safety bearing-wheelslen h of the frame be 30, the axles. 28 being adjustable so that thewheels 30 inay be elevated or depressed to engage the soil,as clearlyshown in Figs. 4,5, 6 and 7. The axles 28 can be adjusted so as r tolift and maintain the belt 6 entirely clear of the ground, whenexpedient; such, for instance, being desirable when the operator wishesto economize fuel by taking advantage of gravity to coast down grade,during which adjustment the vehicle would be supported by the steeringwheels and the bearing wheels 30.

Any desirable means may be employed for adjusting the axles'28, suchbeing shown in this instance as comprising a rack bar 32 slidable inbearing 33, by means of a pinion 34, thesepinions being secured upon atransverse shaft 35, turnableby means-of a wormwhee'l 36', worm"37,"andhandle 38. The lower. end of each bar 32 passes through a slot 39 in theaxle 28, and has a lock-nut 40 at its lower end. 'A strong spring 41surrounds each bar 32 which carries a collar42 between which and an axle28 the spring reacts, thus forming are'silient bearing for the pivotedaxles on each side of the engine.

In order to permit of the individual and opposite adjustment, ifdesired, of the axles, one of the rack bars 32 is provided with a yokeorbracket 43, in which is slidable a rackblock 44, mounted upon a crank45, which is provided with a handle 46, whereby the crank may be t-urnedso that the rack bar 32 may be shifted to enable either rack 32 or 32 tobe intermeshed with pinion 34. Thus when rack 32' is in engagement withpinion 34, the axles 28 will be movable in opposite directions, whereaswhen the racks 32*, mesh with the inions 34, they will work in the samedirection, 71. 6., upwardly or downwardly together. By this mechanism,the axles 28 may be readily adjusted to suit all normal requirements andorchards, and the engine is susceptible to such other adjustments asare-highly conducive to the best results.

The engine embodied in this invention, and actually constructed, is lessthan five feet in width, is simple, of few parts, and is particularlyuseful under theconditions stated. A driven side wheel 50 is journaledupon an A-shaped frame 51 which is removably attached to the main beams2, Fig. 1, so that the wheel 50 has a position well out from the sideand about centrally of the right-hand side of the machinegandwhen it isadjusted toizfl fitend from hauling a plow, the left-hand side; Thoughit is not necesone on each bar 32, are in.

existing in vineyards 2. The frame 51 may olted upon either side of themachine sary to do so, the safety wheels 30 and their axles 28 may bedisconnected at the pivots tended to use the engine in an orchard orvineyard, a minimum width is desirable, and then the safety wheels 30will maintain the engine in equilibrium. The side wheel 50 is securedto, a shaft 52 mounted in the frame 51,.and the shaft 52 is adapted tobe coupled to a transverse shaft 53 journaled in the main frame 2 andcarrying a sprocket 54 driven by a chain 55 running over a pinion56secured to an internal spur gear 57 mounted on an adjustable stud 58so as to be engaged and disengaged with a pinion 59 fastened upon shaft22.- The short transverse shaft 53 projects slightly from each side ofthe frame 2 so that the shaft 52 carrying the side wheel 50 may readilybe coupled when the frame 51 is attached.

By means of the adjustable gear 57 power may be transmittedintermittently to the shaft .53, thus economizing power when the sidewheel 50 is not attached; and I have provided, surrounding the internalgear 57, a simple band brake 60, by means of which, when the gear 57 hasbeen disengaged from pinion 59, the gear 57 and the wheel 50 may be heldrigidly against rotation, and consequently if the main traction wheel 6is driven, the machine will turn about the now fixed wheel 50 as apivot. This is a ve important advantage in a machine of this type. I

It is understood that any preferred form of steering wheel may beemployed, and I have found that the well-known turn-table wheel 4presents the advantage, when the engine is being operated over hard,lumpy ground, of forming a preliminary breaker or crusher, producing asomewhat smoothed bed for the following platform wheel 6. Again, I havefound that a pair of well separated wheels 4 are of value in softyielding ground, as they ofi'era broad two-point support for theforwardend of the machine, giving it, more stability, a much desiredquality.

In addition to the yielding, balancing support furnished bythe safetywheels 30,

thetruck 13 is adapted to have a relatively free yielding action bymeans of the springs 13, the-longitudinal movement of the truck beinglimited by the pins 13 which are rigidly fastened to the sill 2 andproject through suitable openings in the truck.

The necessity of a yielding truck 13 is apparent when the engine isbeing repelled over rolling ground, as indicated by the fieiiible trackbelt passing around and 2 ed by the sprockets, a truck travelingcurt-he? dotted line a, Fig. 2. Under this condition the steering wheelor wheels will be on the descending side of an incline, while thedriving tractor will be ascending, and if the truck was rigidlyconnected to the frame 2 almost the entire weight would be imposed uponthe first roller 13 and upon the individual shoe of the tractor at, theinstant under the roller." Manifestly then, by the provision of theyieldable truck 13 the load is distributed evenly to the rollers, andthe life of the parts much increased, and chance of breakage or injuryreduced.

In Fig. 9 is shown the mechanism for driving the countershaft 53. Italso shows the engine equipped with a steam set, which is preferred insome countries where coal is plentiful and cheap and gasoline is not extensively used.

Fig. 10 shows a slightly modified drive for the side wheel 50, in whichthe pinion '56 .is loosely mounted on the counter shaft 22 and may becoupled thereto by the clutch 61.

lFhe engine I have provided embodies peculiar construction and design,which make it exceptionally useful in the transportation of freight oras a vehicle of commerce in the far northern regions where snow and iceabound so much of the year and the roads are obliterated. i

In the machine illustrated a single endless flexible traction member isshown as the machine is designed primarily for work in narrow spaces butit is obvious that for ordinary traction work the machine would beequipped with duplicate traction members each with its individual truck.

1 The truck frame is a rigid frame and is guided to move in a verticalplane parallel with the/ line of travel of the machine. The

springs/ or resilient supports are interposed between the truck and malnframes to nornlally hold the bottom or bearing portions of the truckbelow the level of the sprocket wheels whereby the truck carries theload of the engine while the sprocket wheels are supported in theirbearings and carry no part of the vehicle load. v

. With the construction described it will be seen that the truck is soheld that it is permitted to yield upwardly bodily or at either end, butthe longitudinal and lateral movements of the truck are limited so astoretain the truck in proper relation to the ground run of the track belt.

Having thus described my invention, what I claim and desire to secure byLetters- Patent is 1. In a vehicle, the combination with a frame andsteering wheel, of a driver embodying front and rear sprockets supportedin bearings and themselves supporting no part of the weight of thevehicle, an endless guide-1 ground run of the belt andhaving an extendedoperative face normallyin a plane below the level of the sprocketswhereby the truck carries the weight of the vehicle, and resilient meansinterposed between the truck and frame to permit the truck to yieldupwardly bodily or at either end.

2. In a vehicle, the combination with a frame and steering Wheel, of adriver embodying front and rear sprockets supported in bearings andthemselves supporting no part of the weight of the vehicle, an endlessflexible traction member passing around and guided by the sprockets, arigid truck extending longitudinally between the sprocket on the groundrun of the traction member, and having its traction member engaging facenormally in a plane below a plane tangent to the bottom of thesprockets, whereby the truck carries the weight of the vehicle,resilient means interposed between the truck and frame to permit thetruck to yield upwardly bodily or at either end, and means for limiting.the longitudinal and lateral movements of the truck.

3. In a vehicle, the combination with a frame, of front and rearsprockets in line on the frame and themselves supporting no part of theload, an endless flexible track' I belt passing around the sprockets,atruck traveling on the ground run of the belt, springs interposedbetween the truck and frame to permit the truck to have a rocking andbodily'yielding upward movement independent of the sprockets, rollersinterposed. between the under side of the truck and the ground run ofthe belt, said truck supporting the load and preventing the portion ofthe-ground run of the belt on which the truck runs from buckling upward.

4.- The combination with a vehicle frame andfront and rear wheels inline and journaled onthe frame, of supporting means therefor; saidsupporting means including an endless belt passing over said Wheels withthe lower run in contact with the ground,

and a verticallymovable rigid truck-inside the belt and between thewheels and having spring connections with the frame to perm'it of ayielding oscillating movement of the truck independent of said wheelsand frame, and against the under side of which truck the backof theground run of the belt operates, said truck being so positioned withrespect to said wheels-that the truck projects below the level of thebottom of the I able rigid truck inside the belt and between the wheelsand having a yielding oscillating movement independent of sald wheels,

and against the under side'of which truck th'eback of the ground run ofthe belt operates; means for preventing the fore and either direction,said truck and not the wheels supporting the load.

6. In a traction engine, the combination of a frame, a? verticallymovable spring pressed truck iyieldingly. supporting the frame, frontand rear wheels in the plane of the truck, and supported above thelevelof the bottom of the truck, the rearmostjone of said wheels beingournaled on the frame independently of the truck, an endless, flexibletraction member passing around said wheels and underneath the truck,with the ground run of the traction member'supporting the,

, truck, and meansfor applying power to said rear wheel to operate thetraction member,

the construct-ionbeing such as to permit the truck to yield upwardlybodily or at'either end. V 7. In a self-propelled vehicle, the c'ombi-,

I nation of a main frame having a front steering wheel and a single reartractor, approximately centrally disposed beneath the frame, and ofrelatively narrow width compared with the width of the frame, saidtractor comprising an endless, flexible, articulated traction member;front and rear sprockets in line on the frame around which the mem-- hertravels, a rigid truckinside the belt 'h'a'ving-rollers bearing on thegroundrun ofth'e traction member, said truckl connected to cross pieceswhich extend to each side of the frame, and individual springs betweenthe ends of the cross pieces and the frame yieldingly supporting theframe, and side hearing wheels connected with the frame to maintain themachine in upright position.

8. Thecombination in a tractionengine, of an engine frame, a truckcomprising a rigid beam-like construction having its greatest dimensionin the direction of its length," and extending parallel with theengineframe, an endless, flexible, articulated traction belt surroundingand infthe plane of the truck, front and rear sprockets on the frame,which sprockets are independent of the truck, and around which the beltpasses, rollers on the truck bearing on the ground run of the belt, theportion of the beltwhich is in contact with the rollers being below thelowest points of said sprockets, whereby theload is carried by the truckand rollers and not by the sprockets, a plurality of s rings interposed.between the truck and frame, alongthe length of the truck to yieldinglysupport the frame on the truck to permit it to yield upwardly bodily orat either end, and means to limit the fore and aft movements of thetruck.

In testimony whereof I- have hereunto set my hand in the presence of twosubscribing witnesses.

G. A; DIoKENsoN, i F. H.. CHIsHoLM.

